Clear coating Carbon Fiber question

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#1

I completed my third vacuum infusion for a project I’m working on and I’m quite pleased with the results… For this particular project, the side of the CF stack that I’d like to show off (clear coat & finish to a high gloss to show the CF 2x2 weave) is the side next to the consumables. In other words the surface that I’d like to finish to a high gloss had the red stripe peel ply against it thus the CF has a textured surface. Today I lightly sanded with 220 grit paper and noticed a good amount of black carbon dust… it was then that I realized sanding might not have been the best idea. I’m thinking I should have cleared right over top of the peel ply textured surface and then sanded the clear coat instead. That said, what brand/part number (be specific) clear coat do you guys recommend. What process do you recommend to finish the textured surfact to a high gloss? Can I clear right over the CF even if my light sanding exposed some of the fibers? (please be specific as I’m a newb). Note that the CF surface will never see direct sunlight so I dont beleive I need UV protectant clear coat… or do I??? This project is for the inner wheel wells on an experemental aircraft… the aircraft will eventually be painted with Imron 3 stage paint so I’d like to use a compatable clear coat if possible (or maybe I should be using THE very same clear that I will be clear coatig the aircraft with???) … Any advice you might be able to offer will be greatly appreciated!

Thx!

James

PS… I’ll post some pics tomorrow…

#2

You can shoot right over any sanded carbon fibers. In the future you might consider adding a “sacrificial” light layer of glass on top of the carbon when infusion. This will give you a little something to sand on before you hit the carbon fiber.

I use PPG Deltron DC3000 for a clear coat.

#3

PPG Deltron DC3000…good stuff. Their 2000 system is super fast to use and requires no post heat cure. Not to mention it has no flash wait time between coats.

#4

The DC3000 (high velocity) cures at room temp in 1.5 hours…and you can start polishing. Add heat or IR waves and you can polish in 30 minutes after shooting. The DC2000 is the Ultra Velocity. 30 minutes at room temp and you can start polishing. Bake it for 15 minutes and your good to go.

Booth are $$$$$$$ though.

#5

I had a simmular experience. I had to make a tube/pipe. So I constructed in a way that is totally taboo. I rolled a sheet of carbon over a mandrel, much like toilet paper on a roll. But I did not use any peelply or vac bagging. so when the epoxy cured it had a very rough feel and look. I sanded it till I was sweating blood and obtained a fairly smooth finish, then clear coated it. came out fairly good. There is a saying. “1KG of paint can cover a ton of sh@t”

#6

You can reduce epoxy with mibk and spray it. Cures over night.

#7

I was told a long time go to never ever ever spray epoxy. Isnt it really nasty health and safteywise?

#8

Epoxy isn’t nearly as bad as the isocyanates in most 2K auto urethanes which is a known carcinogen. Most people recommend a fresh air pump system with working with a paint that contains iso’s. A standard respirator is typically not recommended. Here is some health info on iso in paints.

That being said, you need to take proper precautions with both.

#9

With the right protection, you can spray anything.

#10

Having a coat of resin on the laminate is a great sealer and can be prepped for a uerathane clear/ automotive clear of your choice.

I think as long as you didn’t hog into the laminate with the 320 your golden. Usually 320 will clog up and… It’s kinda hard to go too deep.